openstack/cinder
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Merge "CVE-2024-32498: Check for external qcow2 data file"

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Zuul 2024-07-03 20:08:02 +00:00 committed by Gerrit Code Review
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# Copyright 2020 Red Hat, Inc
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
"""
This is a python implementation of virtual disk format inspection routines
gathered from various public specification documents, as well as qemu disk
driver code. It attempts to store and parse the minimum amount of data
required, and in a streaming-friendly manner to collect metadata about
complex-format images.
"""
import struct
from oslo_log import log as logging
LOG = logging.getLogger(__name__)
def chunked_reader(fileobj, chunk_size=512):
while True:
chunk = fileobj.read(chunk_size)
if not chunk:
break
yield chunk
class CaptureRegion(object):
"""Represents a region of a file we want to capture.
A region of a file we want to capture requires a byte offset into
the file and a length. This is expected to be used by a data
processing loop, calling capture() with the most recently-read
chunk. This class handles the task of grabbing the desired region
of data across potentially multiple fractional and unaligned reads.
:param offset: Byte offset into the file starting the region
:param length: The length of the region
"""
def __init__(self, offset, length):
self.offset = offset
self.length = length
self.data = b''
@property
def complete(self):
"""Returns True when we have captured the desired data."""
return self.length == len(self.data)
def capture(self, chunk, current_position):
"""Process a chunk of data.
This should be called for each chunk in the read loop, at least
until complete returns True.
:param chunk: A chunk of bytes in the file
:param current_position: The position of the file processed by the
read loop so far. Note that this will be
the position in the file *after* the chunk
being presented.
"""
read_start = current_position - len(chunk)
if (read_start <= self.offset <= current_position or
self.offset <= read_start <= (self.offset + self.length)):
if read_start < self.offset:
lead_gap = self.offset - read_start
else:
lead_gap = 0
self.data += chunk[lead_gap:]
self.data = self.data[:self.length]
class ImageFormatError(Exception):
"""An unrecoverable image format error that aborts the process."""
pass
class TraceDisabled(object):
"""A logger-like thing that swallows tracing when we do not want it."""
def debug(self, *a, **k):
pass
info = debug
warning = debug
error = debug
class FileInspector(object):
"""A stream-based disk image inspector.
This base class works on raw images and is subclassed for more
complex types. It is to be presented with the file to be examined
one chunk at a time, during read processing and will only store
as much data as necessary to determine required attributes of
the file.
"""
def __init__(self, tracing=False):
self._total_count = 0
# NOTE(danms): The logging in here is extremely verbose for a reason,
# but should never really be enabled at that level at runtime. To
# retain all that work and assist in future debug, we have a separate
# debug flag that can be passed from a manual tool to turn it on.
if tracing:
self._log = logging.getLogger(str(self))
else:
self._log = TraceDisabled()
self._capture_regions = {}
def _capture(self, chunk, only=None):
for name, region in self._capture_regions.items():
if only and name not in only:
continue
if not region.complete:
region.capture(chunk, self._total_count)
def eat_chunk(self, chunk):
"""Call this to present chunks of the file to the inspector."""
pre_regions = set(self._capture_regions.keys())
# Increment our position-in-file counter
self._total_count += len(chunk)
# Run through the regions we know of to see if they want this
# data
self._capture(chunk)
# Let the format do some post-read processing of the stream
self.post_process()
# Check to see if the post-read processing added new regions
# which may require the current chunk.
new_regions = set(self._capture_regions.keys()) - pre_regions
if new_regions:
self._capture(chunk, only=new_regions)
def post_process(self):
"""Post-read hook to process what has been read so far.
This will be called after each chunk is read and potentially captured
by the defined regions. If any regions are defined by this call,
those regions will be presented with the current chunk in case it
is within one of the new regions.
"""
pass
def region(self, name):
"""Get a CaptureRegion by name."""
return self._capture_regions[name]
def new_region(self, name, region):
"""Add a new CaptureRegion by name."""
if self.has_region(name):
# This is a bug, we tried to add the same region twice
raise ImageFormatError('Inspector re-added region %s' % name)
self._capture_regions[name] = region
def has_region(self, name):
"""Returns True if named region has been defined."""
return name in self._capture_regions
@property
def format_match(self):
"""Returns True if the file appears to be the expected format."""
return True
@property
def virtual_size(self):
"""Returns the virtual size of the disk image, or zero if unknown."""
return self._total_count
@property
def actual_size(self):
"""Returns the total size of the file.
This is usually smaller than virtual_size. NOTE: this will only be
accurate if the entire file is read and processed.
"""
return self._total_count
@property
def complete(self):
"""Returns True if we have all the information needed."""
return all(r.complete for r in self._capture_regions.values())
def __str__(self):
"""The string name of this file format."""
return 'raw'
@property
def context_info(self):
"""Return info on amount of data held in memory for auditing.
This is a dict of region:sizeinbytes items that the inspector
uses to examine the file.
"""
return {name: len(region.data) for name, region in
self._capture_regions.items()}
@classmethod
def from_file(cls, filename):
"""Read as much of a file as necessary to complete inspection.
NOTE: Because we only read as much of the file as necessary, the
actual_size property will not reflect the size of the file, but the
amount of data we read before we satisfied the inspector.
Raises ImageFormatError if we cannot parse the file.
"""
inspector = cls()
with open(filename, 'rb') as f:
for chunk in chunked_reader(f):
inspector.eat_chunk(chunk)
if inspector.complete:
# No need to eat any more data
break
if not inspector.complete or not inspector.format_match:
raise ImageFormatError('File is not in requested format')
return inspector
def safety_check(self):
"""Perform some checks to determine if this file is safe.
Returns True if safe, False otherwise. It may raise ImageFormatError
if safety cannot be guaranteed because of parsing or other errors.
"""
return True
# The qcow2 format consists of a big-endian 72-byte header, of which
# only a small portion has information we care about:
#
# Dec Hex Name
# 0 0x00 Magic 4-bytes 'QFI\xfb'
# 4 0x04 Version (uint32_t, should always be 2 for modern files)
# . . .
# 8 0x08 Backing file offset (uint64_t)
# 24 0x18 Size in bytes (unint64_t)
# . . .
# 72 0x48 Incompatible features bitfield (6 bytes)
#
# https://gitlab.com/qemu-project/qemu/-/blob/master/docs/interop/qcow2.txt
class QcowInspector(FileInspector):
"""QEMU QCOW2 Format
This should only require about 32 bytes of the beginning of the file
to determine the virtual size, and 104 bytes to perform the safety check.
"""
BF_OFFSET = 0x08
BF_OFFSET_LEN = 8
I_FEATURES = 0x48
I_FEATURES_LEN = 8
I_FEATURES_DATAFILE_BIT = 3
I_FEATURES_MAX_BIT = 4
def __init__(self, *a, **k):
super(QcowInspector, self).__init__(*a, **k)
self.new_region('header', CaptureRegion(0, 512))
def _qcow_header_data(self):
magic, version, bf_offset, bf_sz, cluster_bits, size = (
struct.unpack('>4sIQIIQ', self.region('header').data[:32]))
return magic, size
@property
def has_header(self):
return self.region('header').complete
@property
def virtual_size(self):
if not self.region('header').complete:
return 0
if not self.format_match:
return 0
magic, size = self._qcow_header_data()
return size
@property
def format_match(self):
if not self.region('header').complete:
return False
magic, size = self._qcow_header_data()
return magic == b'QFI\xFB'
@property
def has_backing_file(self):
if not self.region('header').complete:
return None
if not self.format_match:
return False
bf_offset_bytes = self.region('header').data[
self.BF_OFFSET:self.BF_OFFSET + self.BF_OFFSET_LEN]
# nonzero means "has a backing file"
bf_offset, = struct.unpack('>Q', bf_offset_bytes)
return bf_offset != 0
@property
def has_unknown_features(self):
if not self.region('header').complete:
return None
if not self.format_match:
return False
i_features = self.region('header').data[
self.I_FEATURES:self.I_FEATURES + self.I_FEATURES_LEN]
# This is the maximum byte number we should expect any bits to be set
max_byte = self.I_FEATURES_MAX_BIT // 8
# The flag bytes are in big-endian ordering, so if we process
# them in index-order, they're reversed
for i, byte_num in enumerate(reversed(range(self.I_FEATURES_LEN))):
if byte_num == max_byte:
# If we're in the max-allowed byte, allow any bits less than
# the maximum-known feature flag bit to be set
allow_mask = ((1 << self.I_FEATURES_MAX_BIT) - 1)
elif byte_num > max_byte:
# If we're above the byte with the maximum known feature flag
# bit, then we expect all zeroes
allow_mask = 0x0
else:
# Any earlier-than-the-maximum byte can have any of the flag
# bits set
allow_mask = 0xFF
if i_features[i] & ~allow_mask:
LOG.warning('Found unknown feature bit in byte %i: %s/%s',
byte_num, bin(i_features[byte_num] & ~allow_mask),
bin(allow_mask))
return True
return False
@property
def has_data_file(self):
if not self.region('header').complete:
return None
if not self.format_match:
return False
i_features = self.region('header').data[
self.I_FEATURES:self.I_FEATURES + self.I_FEATURES_LEN]
# First byte of bitfield, which is i_features[7]
byte = self.I_FEATURES_LEN - 1 - self.I_FEATURES_DATAFILE_BIT // 8
# Third bit of bitfield, which is 0x04
bit = 1 << (self.I_FEATURES_DATAFILE_BIT - 1 % 8)
return bool(i_features[byte] & bit)
def __str__(self):
return 'qcow2'
def safety_check(self):
return (not self.has_backing_file and
not self.has_data_file and
not self.has_unknown_features)
def safety_check_allow_backing_file(self):
return (not self.has_data_file and
not self.has_unknown_features)
class QEDInspector(FileInspector):
def __init__(self, tracing=False):
super().__init__(tracing)
self.new_region('header', CaptureRegion(0, 512))
@property
def format_match(self):
if not self.region('header').complete:
return False
return self.region('header').data.startswith(b'QED\x00')
def safety_check(self):
# QED format is not supported by anyone, but we want to detect it
# and mark it as just always unsafe.
return False
# The VHD (or VPC as QEMU calls it) format consists of a big-endian
# 512-byte "footer" at the beginning of the file with various
# information, most of which does not matter to us:
#
# Dec Hex Name
# 0 0x00 Magic string (8-bytes, always 'conectix')
# 40 0x28 Disk size (uint64_t)
#
# https://github.com/qemu/qemu/blob/master/block/vpc.c
class VHDInspector(FileInspector):
"""Connectix/MS VPC VHD Format
This should only require about 512 bytes of the beginning of the file
to determine the virtual size.
"""
def __init__(self, *a, **k):
super(VHDInspector, self).__init__(*a, **k)
self.new_region('header', CaptureRegion(0, 512))
@property
def format_match(self):
return self.region('header').data.startswith(b'conectix')
@property
def virtual_size(self):
if not self.region('header').complete:
return 0
if not self.format_match:
return 0
return struct.unpack('>Q', self.region('header').data[40:48])[0]
def __str__(self):
return 'vhd'
# The VHDX format consists of a complex dynamic little-endian
# structure with multiple regions of metadata and data, linked by
# offsets with in the file (and within regions), identified by MSFT
# GUID strings. The header is a 320KiB structure, only a few pieces of
# which we actually need to capture and interpret:
#
# Dec Hex Name
# 0 0x00000 Identity (Technically 9-bytes, padded to 64KiB, the first
# 8 bytes of which are 'vhdxfile')
# 196608 0x30000 The Region table (64KiB of a 32-byte header, followed
# by up to 2047 36-byte region table entry structures)
#
# The region table header includes two items we need to read and parse,
# which are:
#
# 196608 0x30000 4-byte signature ('regi')
# 196616 0x30008 Entry count (uint32-t)
#
# The region table entries follow the region table header immediately
# and are identified by a 16-byte GUID, and provide an offset of the
# start of that region. We care about the "metadata region", identified
# by the METAREGION class variable. The region table entry is (offsets
# from the beginning of the entry, since it could be in multiple places):
#
# 0 0x00000 16-byte MSFT GUID
# 16 0x00010 Offset of the actual metadata region (uint64_t)
#
# When we find the METAREGION table entry, we need to grab that offset
# and start examining the region structure at that point. That
# consists of a metadata table of structures, which point to places in
# the data in an unstructured space that follows. The header is
# (offsets relative to the region start):
#
# 0 0x00000 8-byte signature ('metadata')
# . . .
# 16 0x00010 2-byte entry count (up to 2047 entries max)
#
# This header is followed by the specified number of metadata entry
# structures, identified by GUID:
#
# 0 0x00000 16-byte MSFT GUID
# 16 0x00010 4-byte offset (uint32_t, relative to the beginning of
# the metadata region)
#
# We need to find the "Virtual Disk Size" metadata item, identified by
# the GUID in the VIRTUAL_DISK_SIZE class variable, grab the offset,
# add it to the offset of the metadata region, and examine that 8-byte
# chunk of data that follows.
#
# The "Virtual Disk Size" is a naked uint64_t which contains the size
# of the virtual disk, and is our ultimate target here.
#
# https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-vhdx/83e061f8-f6e2-4de1-91bd-5d518a43d477
class VHDXInspector(FileInspector):
"""MS VHDX Format
This requires some complex parsing of the stream. The first 256KiB
of the image is stored to get the header and region information,
and then we capture the first metadata region to read those
records, find the location of the virtual size data and parse
it. This needs to store the metadata table entries up until the
VDS record, which may consist of up to 2047 32-byte entries at
max. Finally, it must store a chunk of data at the offset of the
actual VDS uint64.
"""
METAREGION = '8B7CA206-4790-4B9A-B8FE-575F050F886E'
VIRTUAL_DISK_SIZE = '2FA54224-CD1B-4876-B211-5DBED83BF4B8'
VHDX_METADATA_TABLE_MAX_SIZE = 32 * 2048 # From qemu
def __init__(self, *a, **k):
super(VHDXInspector, self).__init__(*a, **k)
self.new_region('ident', CaptureRegion(0, 32))
self.new_region('header', CaptureRegion(192 * 1024, 64 * 1024))
def post_process(self):
# After reading a chunk, we may have the following conditions:
#
# 1. We may have just completed the header region, and if so,
# we need to immediately read and calculate the location of
# the metadata region, as it may be starting in the same
# read we just did.
# 2. We may have just completed the metadata region, and if so,
# we need to immediately calculate the location of the
# "virtual disk size" record, as it may be starting in the
# same read we just did.
if self.region('header').complete and not self.has_region('metadata'):
region = self._find_meta_region()
if region:
self.new_region('metadata', region)
elif self.has_region('metadata') and not self.has_region('vds'):
region = self._find_meta_entry(self.VIRTUAL_DISK_SIZE)
if region:
self.new_region('vds', region)
@property
def format_match(self):
return self.region('ident').data.startswith(b'vhdxfile')
@staticmethod
def _guid(buf):
"""Format a MSFT GUID from the 16-byte input buffer."""
guid_format = '<IHHBBBBBBBB'
return '%08X-%04X-%04X-%02X%02X-%02X%02X%02X%02X%02X%02X' % (
struct.unpack(guid_format, buf))
def _find_meta_region(self):
# The region table entries start after a 16-byte table header
region_entry_first = 16
# Parse the region table header to find the number of regions
regi, cksum, count, reserved = struct.unpack(
'<IIII', self.region('header').data[:16])
if regi != 0x69676572:
raise ImageFormatError('Region signature not found at %x' % (
self.region('header').offset))
if count >= 2048:
raise ImageFormatError('Region count is %i (limit 2047)' % count)
# Process the regions until we find the metadata one; grab the
# offset and return
self._log.debug('Region entry first is %x', region_entry_first)
self._log.debug('Region entries %i', count)
meta_offset = 0
for i in range(0, count):
entry_start = region_entry_first + (i * 32)
entry_end = entry_start + 32
entry = self.region('header').data[entry_start:entry_end]
self._log.debug('Entry offset is %x', entry_start)
# GUID is the first 16 bytes
guid = self._guid(entry[:16])
if guid == self.METAREGION:
# This entry is the metadata region entry
meta_offset, meta_len, meta_req = struct.unpack(
'<QII', entry[16:])
self._log.debug('Meta entry %i specifies offset: %x',
i, meta_offset)
# NOTE(danms): The meta_len in the region descriptor is the
# entire size of the metadata table and data. This can be
# very large, so we should only capture the size required
# for the maximum length of the table, which is one 32-byte
# table header, plus up to 2047 32-byte entries.
meta_len = 2048 * 32
return CaptureRegion(meta_offset, meta_len)
self._log.warning('Did not find metadata region')
return None
def _find_meta_entry(self, desired_guid):
meta_buffer = self.region('metadata').data
if len(meta_buffer) < 32:
# Not enough data yet for full header
return None
# Make sure we found the metadata region by checking the signature
sig, reserved, count = struct.unpack('<8sHH', meta_buffer[:12])
if sig != b'metadata':
raise ImageFormatError(
'Invalid signature for metadata region: %r' % sig)
entries_size = 32 + (count * 32)
if len(meta_buffer) < entries_size:
# Not enough data yet for all metadata entries. This is not
# strictly necessary as we could process whatever we have until
# we find the V-D-S one, but there are only 2047 32-byte
# entries max (~64k).
return None
if count >= 2048:
raise ImageFormatError(
'Metadata item count is %i (limit 2047)' % count)
for i in range(0, count):
entry_offset = 32 + (i * 32)
guid = self._guid(meta_buffer[entry_offset:entry_offset + 16])
if guid == desired_guid:
# Found the item we are looking for by id.
# Stop our region from capturing
item_offset, item_length, _reserved = struct.unpack(
'<III',
meta_buffer[entry_offset + 16:entry_offset + 28])
item_length = min(item_length,
self.VHDX_METADATA_TABLE_MAX_SIZE)
self.region('metadata').length = len(meta_buffer)
self._log.debug('Found entry at offset %x', item_offset)
# Metadata item offset is from the beginning of the metadata
# region, not the file.
return CaptureRegion(
self.region('metadata').offset + item_offset,
item_length)
self._log.warning('Did not find guid %s', desired_guid)
return None
@property
def virtual_size(self):
# Until we have found the offset and have enough metadata buffered
# to read it, return "unknown"
if not self.has_region('vds') or not self.region('vds').complete:
return 0
size, = struct.unpack('<Q', self.region('vds').data)
return size
def __str__(self):
return 'vhdx'
# The VMDK format comes in a large number of variations, but the
# single-file 'monolithicSparse' version 4 one is mostly what we care
# about. It contains a 512-byte little-endian header, followed by a
# variable-length "descriptor" region of text. The header looks like:
#
# Dec Hex Name
# 0 0x00 4-byte magic string 'KDMV'
# 4 0x04 Version (uint32_t)
# 8 0x08 Flags (uint32_t, unused by us)
# 16 0x10 Number of 512 byte sectors in the disk (uint64_t)
# 24 0x18 Granularity (uint64_t, unused by us)
# 32 0x20 Descriptor offset in 512-byte sectors (uint64_t)
# 40 0x28 Descriptor size in 512-byte sectors (uint64_t)
#
# After we have the header, we need to find the descriptor region,
# which starts at the sector identified in the "descriptor offset"
# field, and is "descriptor size" 512-byte sectors long. Once we have
# that region, we need to parse it as text, looking for the
# createType=XXX line that specifies the mechanism by which the data
# extents are stored in this file. We only support the
# "monolithicSparse" format, so we just need to confirm that this file
# contains that specifier.
#
# https://www.vmware.com/app/vmdk/?src=vmdk
class VMDKInspector(FileInspector):
"""vmware VMDK format (monolithicSparse and streamOptimized variants only)
This needs to store the 512 byte header and the descriptor region
which should be just after that. The descriptor region is some
variable number of 512 byte sectors, but is just text defining the
layout of the disk.
"""
# The beginning and max size of the descriptor is also hardcoded in Qemu
# at 0x200 and 1MB - 1
DESC_OFFSET = 0x200
DESC_MAX_SIZE = (1 << 20) - 1
GD_AT_END = 0xffffffffffffffff
def __init__(self, *a, **k):
super(VMDKInspector, self).__init__(*a, **k)
self.new_region('header', CaptureRegion(0, 512))
def post_process(self):
# If we have just completed the header region, we need to calculate
# the location and length of the descriptor, which should immediately
# follow and may have been partially-read in this read.
if not self.region('header').complete:
return
(sig, ver, _flags, _sectors, _grain, desc_sec, desc_num,
_numGTEsperGT, _rgdOffset, gdOffset) = struct.unpack(
'<4sIIQQQQIQQ', self.region('header').data[:64])
if sig != b'KDMV':
raise ImageFormatError('Signature KDMV not found: %r' % sig)
if ver not in (1, 2, 3):
raise ImageFormatError('Unsupported format version %i' % ver)
if gdOffset == self.GD_AT_END:
# This means we have a footer, which takes precedence over the
# header, which we cannot support since we stream.
raise ImageFormatError('Unsupported VMDK footer')
# Since we parse both desc_sec and desc_num (the location of the
# VMDK's descriptor, expressed in 512 bytes sectors) we enforce a
# check on the bounds to create a reasonable CaptureRegion. This
# is similar to how it's done in qemu.
desc_offset = desc_sec * 512
desc_size = min(desc_num * 512, self.DESC_MAX_SIZE)
if desc_offset != self.DESC_OFFSET:
raise ImageFormatError("Wrong descriptor location")
if not self.has_region('descriptor'):
self.new_region('descriptor', CaptureRegion(
desc_offset, desc_size))
@property
def format_match(self):
return self.region('header').data.startswith(b'KDMV')
@property
def virtual_size(self):
if not self.has_region('descriptor'):
# Not enough data yet
return 0
descriptor_rgn = self.region('descriptor')
if not descriptor_rgn.complete:
# Not enough data yet
return 0
descriptor = descriptor_rgn.data
type_idx = descriptor.index(b'createType="') + len(b'createType="')
type_end = descriptor.find(b'"', type_idx)
# Make sure we don't grab and log a huge chunk of data in a
# maliciously-formatted descriptor region
if type_end - type_idx < 64:
vmdktype = descriptor[type_idx:type_end]
else:
vmdktype = b'formatnotfound'
if vmdktype not in (b'monolithicSparse', b'streamOptimized'):
LOG.warning('Unsupported VMDK format %s', vmdktype)
return 0
# If we have the descriptor, we definitely have the header
_sig, _ver, _flags, sectors, _grain, _desc_sec, _desc_num = (
struct.unpack('<IIIQQQQ', self.region('header').data[:44]))
return sectors * 512
def safety_check(self):
if (not self.has_region('descriptor') or
not self.region('descriptor').complete):
return False
try:
# Descriptor is padded to 512 bytes
desc_data = self.region('descriptor').data.rstrip(b'\x00')
# Descriptor is actually case-insensitive ASCII text
desc_text = desc_data.decode('ascii').lower()
except UnicodeDecodeError:
LOG.error('VMDK descriptor failed to decode as ASCII')
raise ImageFormatError('Invalid VMDK descriptor data')
extent_access = ('rw', 'rdonly', 'noaccess')
header_fields = []
extents = []
ddb = []
# NOTE(danms): Cautiously parse the VMDK descriptor. Each line must
# be something we understand, otherwise we refuse it.
for line in [x.strip() for x in desc_text.split('\n')]:
if line.startswith('#') or not line:
# Blank or comment lines are ignored
continue
elif line.startswith('ddb'):
# DDB lines are allowed (but not used by us)
ddb.append(line)
elif '=' in line and ' ' not in line.split('=')[0]:
# Header fields are a single word followed by an '=' and some
# value
header_fields.append(line)
elif line.split(' ')[0] in extent_access:
# Extent lines start with one of the three access modes
extents.append(line)
else:
# Anything else results in a rejection
LOG.error('Unsupported line %r in VMDK descriptor', line)
raise ImageFormatError('Invalid VMDK descriptor data')
# Check all the extent lines for concerning content
for extent_line in extents:
if '/' in extent_line:
LOG.error('Extent line %r contains unsafe characters',
extent_line)
return False
if not extents:
LOG.error('VMDK file specified no extents')
return False
return True
def __str__(self):
return 'vmdk'
# The VirtualBox VDI format consists of a 512-byte little-endian
# header, some of which we care about:
#
# Dec Hex Name
# 64 0x40 4-byte Magic (0xbeda107f)
# . . .
# 368 0x170 Size in bytes (uint64_t)
#
# https://github.com/qemu/qemu/blob/master/block/vdi.c
class VDIInspector(FileInspector):
"""VirtualBox VDI format
This only needs to store the first 512 bytes of the image.
"""
def __init__(self, *a, **k):
super(VDIInspector, self).__init__(*a, **k)
self.new_region('header', CaptureRegion(0, 512))
@property
def format_match(self):
if not self.region('header').complete:
return False
signature, = struct.unpack('<I', self.region('header').data[0x40:0x44])
return signature == 0xbeda107f
@property
def virtual_size(self):
if not self.region('header').complete:
return 0
if not self.format_match:
return 0
size, = struct.unpack('<Q', self.region('header').data[0x170:0x178])
return size
def __str__(self):
return 'vdi'
class InfoWrapper(object):
"""A file-like object that wraps another and updates a format inspector.
This passes chunks to the format inspector while reading. If the inspector
fails, it logs the error and stops calling it, but continues proxying data
from the source to its user.
"""
def __init__(self, source, fmt):
self._source = source
self._format = fmt
self._error = False
def __iter__(self):
return self
def _process_chunk(self, chunk):
if not self._error:
try:
self._format.eat_chunk(chunk)
except Exception as e:
# Absolutely do not allow the format inspector to break
# our streaming of the image. If we failed, just stop
# trying, log and keep going.
LOG.error('Format inspector failed, aborting: %s', e)
self._error = True
def __next__(self):
try:
chunk = next(self._source)
except StopIteration:
raise
self._process_chunk(chunk)
return chunk
def read(self, size):
chunk = self._source.read(size)
self._process_chunk(chunk)
return chunk
def close(self):
if hasattr(self._source, 'close'):
self._source.close()
ALL_FORMATS = {
'raw': FileInspector,
'qcow2': QcowInspector,
'vhd': VHDInspector,
'vhdx': VHDXInspector,
'vmdk': VMDKInspector,
'vdi': VDIInspector,
'qed': QEDInspector,
}
def get_inspector(format_name):
"""Returns a FormatInspector class based on the given name.
:param format_name: The name of the disk_format (raw, qcow2, etc).
:returns: A FormatInspector or None if unsupported.
"""
return ALL_FORMATS.get(format_name)
def detect_file_format(filename):
"""Attempts to detect the format of a file.
This runs through a file one time, running all the known inspectors in
parallel. It stops reading the file once one of them matches or all of
them are sure they don't match.
Returns the FileInspector that matched, if any. None if 'raw'.
"""
inspectors = {k: v() for k, v in ALL_FORMATS.items()}
with open(filename, 'rb') as f:
for chunk in chunked_reader(f):
for format, inspector in list(inspectors.items()):
try:
inspector.eat_chunk(chunk)
except ImageFormatError:
# No match, so stop considering this format
inspectors.pop(format)
continue
if (inspector.format_match and inspector.complete and
format != 'raw'):
# First complete match (other than raw) wins
return inspector
if all(i.complete for i in inspectors.values()):
# If all the inspectors are sure they are not a match, avoid
# reading to the end of the file to settle on 'raw'.
break
return inspectors['raw']

84
cinder/image/image_utils.py
View File

@ -52,6 +52,7 @@ from cinder import exception
from cinder.i18n import _
from cinder.image import accelerator
from cinder.image import glance
import cinder.privsep.format_inspector
from cinder import utils
from cinder.volume import throttling
from cinder.volume import volume_utils
@ -158,11 +159,26 @@ def from_qemu_img_disk_format(disk_format: str) -> str:
return QEMU_IMG_FORMAT_MAP_INV.get(disk_format, disk_format)
def qemu_img_info(path: str,
def qemu_img_info(
path: str,
run_as_root: bool = True,
force_share: bool = False) -> imageutils.QemuImgInfo:
force_share: bool = False,
allow_qcow2_backing_file: bool = False) -> imageutils.QemuImgInfo:
"""Return an object containing the parsed output from qemu-img info."""
cmd = ['env', 'LC_ALL=C', 'qemu-img', 'info', '--output=json']
format_name = cinder.privsep.format_inspector.get_format_if_safe(
path=path,
allow_qcow2_backing_file=allow_qcow2_backing_file)
if format_name is None:
LOG.warning('Image/Volume %s failed safety check', path)
# NOTE(danms): This is the same exception as would be raised
# by qemu_img_info() if the disk format was unreadable or
# otherwise unsuitable.
raise exception.Invalid(
reason=_('Image/Volume failed safety check'))
cmd = ['env', 'LC_ALL=C', 'qemu-img', 'info',
'-f', format_name, '--output=json']
if force_share:
cmd.append('--force-share')
cmd.append(path)
@ -173,8 +189,32 @@ def qemu_img_info(path: str,
prlimit=QEMU_IMG_LIMITS)
info = imageutils.QemuImgInfo(out, format='json')
# FIXME: figure out a more elegant way to do this
if info.file_format == 'raw':
# The format_inspector will detect a luks image as 'raw', and then when
# we call qemu-img info -f raw above, we don't get any of the luks
# format-specific info (some of which is used in the create_volume
# flow). So we need to check if this is really a luks container.
# (We didn't have to do this in the past because we called
# qemu-img info without -f.)
cmd = ['env', 'LC_ALL=C', 'qemu-img', 'info',
'-f', 'luks', '--output=json']
if force_share:
cmd.append('--force-share')
cmd.append(path)
if os.name == 'nt':
cmd = cmd[2:]
try:
out, _err = utils.execute(*cmd, run_as_root=run_as_root,
prlimit=QEMU_IMG_LIMITS)
info = imageutils.QemuImgInfo(out, format='json')
except processutils.ProcessExecutionError:
# we'll just use the info object we already got earlier
pass
# From Cinder's point of view, any 'luks' formatted images
# should be treated as 'raw'.
# should be treated as 'raw'. (This changes the file_format, but
# not any of the format-specific information.)
if info.file_format == 'luks':
info.file_format = 'raw'
@ -681,6 +721,35 @@ def get_qemu_data(image_id: str,
return data
def check_qcow2_image(image_id: str, data: imageutils.QemuImgInfo) -> None:
"""Check some rules about qcow2 images.
Does not check for a backing_file, because cinder has some legitimate
use cases for qcow2 backing files.
Makes sure the image:
- does not have a data_file
:param image_id: the image id
:param data: an imageutils.QemuImgInfo object
:raises ImageUnacceptable: when the image fails the check
"""
try:
data_file = data.format_specific['data'].get('data-file')
except (KeyError, TypeError):
LOG.debug('Unexpected response from qemu-img info when processing '
'image %s: missing format-specific info for a qcow2 image',
image_id)
msg = _('Cannot determine format-specific information')
raise exception.ImageUnacceptable(image_id=image_id, reason=msg)
if data_file:
LOG.warning("Refusing to process qcow2 file with data-file '%s'",
data_file)
msg = _('A qcow2 format image is not allowed to have a data file')
raise exception.ImageUnacceptable(image_id=image_id, reason=msg)
def check_vmdk_image(image_id: str, data: imageutils.QemuImgInfo) -> None:
"""Check some rules about VMDK images.
@ -771,6 +840,8 @@ def check_image_format(source: str,
if data.file_format == 'vmdk':
check_vmdk_image(image_id, data)
if data.file_format == 'qcow2':
check_qcow2_image(image_id, data)
def fetch_verify_image(context: context.RequestContext,
@ -813,6 +884,11 @@ def fetch_verify_image(context: context.RequestContext,
if fmt == 'vmdk':
check_vmdk_image(image_id, data)
# Bug #2059809: a qcow2 can have a data file that's similar
# to a backing file and is also unacceptable
if fmt == 'qcow2':
check_qcow2_image(image_id, data)
def fetch_to_vhd(context: context.RequestContext,
image_service: glance.GlanceImageService,

38
cinder/privsep/format_inspector.py Normal file
View File

@ -0,0 +1,38 @@
# Copyright 2024 Red Hat, Inc
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
"""
Helpers for the image format_inspector.
"""
from cinder.image import format_inspector
import cinder.privsep
@cinder.privsep.sys_admin_pctxt.entrypoint
def get_format_if_safe(path, allow_qcow2_backing_file):
"""Returns a str format name if the format is safe, otherwise None"""
return _get_format_if_safe(path, allow_qcow2_backing_file)
def _get_format_if_safe(path, allow_qcow2_backing_file):
"""Returns a str format name if the format is safe, otherwise None"""
inspector = format_inspector.detect_file_format(path)
format_name = str(inspector)
safe = inspector.safety_check()
if not safe and format_name == 'qcow2' and allow_qcow2_backing_file:
safe = inspector.safety_check_allow_backing_file()
if safe:
return format_name

515
cinder/tests/unit/image/test_format_inspector.py Normal file
View File

@ -0,0 +1,515 @@
# Copyright 2020 Red Hat, Inc
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import io
import os
import re
import struct
import subprocess
import tempfile
from unittest import mock
from oslo_utils import units
from cinder.image import format_inspector
from cinder.tests.unit import test
def get_size_from_qemu_img(filename):
output = subprocess.check_output('qemu-img info "%s"' % filename,
shell=True)
for line in output.split(b'\n'):
m = re.search(b'^virtual size: .* .([0-9]+) bytes', line.strip())
if m:
return int(m.group(1))
raise Exception('Could not find virtual size with qemu-img')
class TestFormatInspectors(test.TestCase):
def setUp(self):
super(TestFormatInspectors, self).setUp()
self._created_files = []
def tearDown(self):
super(TestFormatInspectors, self).tearDown()
for fn in self._created_files:
try:
os.remove(fn)
except Exception:
pass
def _create_img(self, fmt, size, subformat=None, options=None,
backing_file=None):
if fmt == 'vhd':
# QEMU calls the vhd format vpc
fmt = 'vpc'
if options is None:
options = {}
opt = ''
prefix = 'glance-unittest-formatinspector-'
if subformat:
options['subformat'] = subformat
prefix += subformat + '-'
if options:
opt += '-o ' + ','.join('%s=%s' % (k, v)
for k, v in options.items())
if backing_file is not None:
opt += ' -b %s -F raw' % backing_file
fn = tempfile.mktemp(prefix=prefix,
suffix='.%s' % fmt)
self._created_files.append(fn)
subprocess.check_output(
'qemu-img create -f %s %s %s %i' % (fmt, opt, fn, size),
shell=True)
return fn
def _create_allocated_vmdk(self, size_mb, subformat=None):
# We need a "big" VMDK file to exercise some parts of the code of the
# format_inspector. A way to create one is to first create an empty
# file, and then to convert it with the -S 0 option.
if subformat is None:
# Matches qemu-img default, see `qemu-img convert -O vmdk -o help`
subformat = 'monolithicSparse'
prefix = 'glance-unittest-formatinspector-%s-' % subformat
fn = tempfile.mktemp(prefix=prefix, suffix='.vmdk')
self._created_files.append(fn)
raw = tempfile.mktemp(prefix=prefix, suffix='.raw')
self._created_files.append(raw)
# Create a file with pseudo-random data, otherwise it will get
# compressed in the streamOptimized format
subprocess.check_output(
'dd if=/dev/urandom of=%s bs=1M count=%i' % (raw, size_mb),
shell=True)
# Convert it to VMDK
subprocess.check_output(
'qemu-img convert -f raw -O vmdk -o subformat=%s -S 0 %s %s' % (
subformat, raw, fn),
shell=True)
return fn
def _test_format_at_block_size(self, format_name, img, block_size):
fmt = format_inspector.get_inspector(format_name)()
self.assertIsNotNone(fmt,
'Did not get format inspector for %s' % (
format_name))
wrapper = format_inspector.InfoWrapper(open(img, 'rb'), fmt)
while True:
chunk = wrapper.read(block_size)
if not chunk:
break
wrapper.close()
return fmt
def _test_format_at_image_size(self, format_name, image_size,
subformat=None):
img = self._create_img(format_name, image_size, subformat=subformat)
# Some formats have internal alignment restrictions making this not
# always exactly like image_size, so get the real value for comparison
virtual_size = get_size_from_qemu_img(img)
# Read the format in various sizes, some of which will read whole
# sections in a single read, others will be completely unaligned, etc.
for block_size in (64 * units.Ki, 512, 17, 1 * units.Mi):
fmt = self._test_format_at_block_size(format_name, img, block_size)
self.assertTrue(fmt.format_match,
'Failed to match %s at size %i block %i' % (
format_name, image_size, block_size))
self.assertEqual(virtual_size, fmt.virtual_size,
('Failed to calculate size for %s at size %i '
'block %i') % (format_name, image_size,
block_size))
memory = sum(fmt.context_info.values())
self.assertLess(memory, 512 * units.Ki,
'Format used more than 512KiB of memory: %s' % (
fmt.context_info))
def _test_format(self, format_name, subformat=None):
# Try a few different image sizes, including some odd and very small
# sizes
for image_size in (512, 513, 2057, 7):
self._test_format_at_image_size(format_name, image_size * units.Mi,
subformat=subformat)
def test_qcow2(self):
self._test_format('qcow2')
def test_vhd(self):
self._test_format('vhd')
def test_vhdx(self):
self._test_format('vhdx')
def test_vmdk(self):
self._test_format('vmdk')
def test_vmdk_stream_optimized(self):
self._test_format('vmdk', 'streamOptimized')
def test_from_file_reads_minimum(self):
img = self._create_img('qcow2', 10 * units.Mi)
file_size = os.stat(img).st_size
fmt = format_inspector.QcowInspector.from_file(img)
# We know everything we need from the first 512 bytes of a QCOW image,
# so make sure that we did not read the whole thing when we inspect
# a local file.
self.assertLess(fmt.actual_size, file_size)
def test_qed_always_unsafe(self):
img = self._create_img('qed', 10 * units.Mi)
fmt = format_inspector.get_inspector('qed').from_file(img)
self.assertTrue(fmt.format_match)
self.assertFalse(fmt.safety_check())
def _test_vmdk_bad_descriptor_offset(self, subformat=None):
format_name = 'vmdk'
image_size = 10 * units.Mi
descriptorOffsetAddr = 0x1c
BAD_ADDRESS = 0x400
img = self._create_img(format_name, image_size, subformat=subformat)
# Corrupt the header
fd = open(img, 'r+b')
fd.seek(descriptorOffsetAddr)
fd.write(struct.pack('<Q', BAD_ADDRESS // 512))
fd.close()
# Read the format in various sizes, some of which will read whole
# sections in a single read, others will be completely unaligned, etc.
for block_size in (64 * units.Ki, 512, 17, 1 * units.Mi):
fmt = self._test_format_at_block_size(format_name, img, block_size)
self.assertTrue(fmt.format_match,
'Failed to match %s at size %i block %i' % (
format_name, image_size, block_size))
self.assertEqual(0, fmt.virtual_size,
('Calculated a virtual size for a corrupt %s at '
'size %i block %i') % (format_name, image_size,
block_size))
def test_vmdk_bad_descriptor_offset(self):
self._test_vmdk_bad_descriptor_offset()
def test_vmdk_bad_descriptor_offset_stream_optimized(self):
self._test_vmdk_bad_descriptor_offset(subformat='streamOptimized')
def _test_vmdk_bad_descriptor_mem_limit(self, subformat=None):
format_name = 'vmdk'
image_size = 5 * units.Mi
virtual_size = 5 * units.Mi
descriptorOffsetAddr = 0x1c
descriptorSizeAddr = descriptorOffsetAddr + 8
twoMBInSectors = (2 << 20) // 512
# We need a big VMDK because otherwise we will not have enough data to
# fill-up the CaptureRegion.
img = self._create_allocated_vmdk(image_size // units.Mi,
subformat=subformat)
# Corrupt the end of descriptor address so it "ends" at 2MB
fd = open(img, 'r+b')
fd.seek(descriptorSizeAddr)
fd.write(struct.pack('<Q', twoMBInSectors))
fd.close()
# Read the format in various sizes, some of which will read whole
# sections in a single read, others will be completely unaligned, etc.
for block_size in (64 * units.Ki, 512, 17, 1 * units.Mi):
fmt = self._test_format_at_block_size(format_name, img, block_size)
self.assertTrue(fmt.format_match,
'Failed to match %s at size %i block %i' % (
format_name, image_size, block_size))
self.assertEqual(virtual_size, fmt.virtual_size,
('Failed to calculate size for %s at size %i '
'block %i') % (format_name, image_size,
block_size))
memory = sum(fmt.context_info.values())
self.assertLess(memory, 1.5 * units.Mi,
'Format used more than 1.5MiB of memory: %s' % (
fmt.context_info))
def test_vmdk_bad_descriptor_mem_limit(self):
self._test_vmdk_bad_descriptor_mem_limit()
def test_vmdk_bad_descriptor_mem_limit_stream_optimized(self):
self._test_vmdk_bad_descriptor_mem_limit(subformat='streamOptimized')
def test_qcow2_safety_checks(self):
# Create backing and data-file names (and initialize the backing file)
backing_fn = tempfile.mktemp(prefix='backing')
self._created_files.append(backing_fn)
with open(backing_fn, 'w') as f:
f.write('foobar')
data_fn = tempfile.mktemp(prefix='data')
self._created_files.append(data_fn)
# A qcow with no backing or data file is safe
fn = self._create_img('qcow2', 5 * units.Mi, None)
inspector = format_inspector.QcowInspector.from_file(fn)
self.assertTrue(inspector.safety_check())
self.assertTrue(inspector.safety_check_allow_backing_file())
# A backing file makes it unsafe
fn = self._create_img('qcow2', 5 * units.Mi, None,
backing_file=backing_fn)
inspector = format_inspector.QcowInspector.from_file(fn)
self.assertFalse(inspector.safety_check())
# ... unless we explictly allow a backing file
self.assertTrue(inspector.safety_check_allow_backing_file())
# A data-file makes it unsafe
fn = self._create_img('qcow2', 5 * units.Mi,
options={'data_file': data_fn,
'data_file_raw': 'on'})
inspector = format_inspector.QcowInspector.from_file(fn)
self.assertFalse(inspector.safety_check())
# ... and it remains unsafe even if we allow a backing file
self.assertFalse(inspector.safety_check_allow_backing_file())
# Trying to load a non-QCOW file is an error
self.assertRaises(format_inspector.ImageFormatError,
format_inspector.QcowInspector.from_file,
backing_fn)
def test_qcow2_feature_flag_checks(self):
data = bytearray(512)
data[0:4] = b'QFI\xFB'
inspector = format_inspector.QcowInspector()
inspector.region('header').data = data
# All zeros, no feature flags - all good
self.assertFalse(inspector.has_unknown_features)
# A feature flag set in the first byte (highest-order) is not
# something we know about, so fail.
data[0x48] = 0x01
self.assertTrue(inspector.has_unknown_features)
# The first bit in the last byte (lowest-order) is known (the dirty
# bit) so that should pass
data[0x48] = 0x00
data[0x4F] = 0x01
self.assertFalse(inspector.has_unknown_features)
# Currently (as of 2024), the high-order feature flag bit in the low-
# order byte is not assigned, so make sure we reject it.
data[0x4F] = 0x80
self.assertTrue(inspector.has_unknown_features)
def test_vdi(self):
self._test_format('vdi')
def _test_format_with_invalid_data(self, format_name):
fmt = format_inspector.get_inspector(format_name)()
wrapper = format_inspector.InfoWrapper(open(__file__, 'rb'), fmt)
while True:
chunk = wrapper.read(32)
if not chunk:
break
wrapper.close()
self.assertFalse(fmt.format_match)
self.assertEqual(0, fmt.virtual_size)
memory = sum(fmt.context_info.values())
self.assertLess(memory, 512 * units.Ki,
'Format used more than 512KiB of memory: %s' % (
fmt.context_info))
def test_qcow2_invalid(self):
self._test_format_with_invalid_data('qcow2')
def test_vhd_invalid(self):
self._test_format_with_invalid_data('vhd')
def test_vhdx_invalid(self):
self._test_format_with_invalid_data('vhdx')
def test_vmdk_invalid(self):
self._test_format_with_invalid_data('vmdk')
def test_vdi_invalid(self):
self._test_format_with_invalid_data('vdi')
def test_vmdk_invalid_type(self):
fmt = format_inspector.get_inspector('vmdk')()
wrapper = format_inspector.InfoWrapper(open(__file__, 'rb'), fmt)
while True:
chunk = wrapper.read(32)
if not chunk:
break
wrapper.close()
fake_rgn = mock.MagicMock()
fake_rgn.complete = True
fake_rgn.data = b'foocreateType="someunknownformat"bar'
with mock.patch.object(fmt, 'has_region', return_value=True):
with mock.patch.object(fmt, 'region', return_value=fake_rgn):
self.assertEqual(0, fmt.virtual_size)
class TestFormatInspectorInfra(test.TestCase):
def _test_capture_region_bs(self, bs):
data = b''.join(chr(x).encode() for x in range(ord('A'), ord('z')))
regions = [
format_inspector.CaptureRegion(3, 9),
format_inspector.CaptureRegion(0, 256),
format_inspector.CaptureRegion(32, 8),
]
for region in regions:
# None of them should be complete yet
self.assertFalse(region.complete)
pos = 0
for i in range(0, len(data), bs):
chunk = data[i:i + bs]
pos += len(chunk)
for region in regions:
region.capture(chunk, pos)
self.assertEqual(data[3:12], regions[0].data)
self.assertEqual(data[0:256], regions[1].data)
self.assertEqual(data[32:40], regions[2].data)
# The small regions should be complete
self.assertTrue(regions[0].complete)
self.assertTrue(regions[2].complete)
# This region extended past the available data, so not complete
self.assertFalse(regions[1].complete)
def test_capture_region(self):
for block_size in (1, 3, 7, 13, 32, 64):
self._test_capture_region_bs(block_size)
def _get_wrapper(self, data):
source = io.BytesIO(data)
fake_fmt = mock.create_autospec(format_inspector.get_inspector('raw'))
return format_inspector.InfoWrapper(source, fake_fmt)
def test_info_wrapper_file_like(self):
data = b''.join(chr(x).encode() for x in range(ord('A'), ord('z')))
wrapper = self._get_wrapper(data)
read_data = b''
while True:
chunk = wrapper.read(8)
if not chunk:
break
read_data += chunk
self.assertEqual(data, read_data)
def test_info_wrapper_iter_like(self):
data = b''.join(chr(x).encode() for x in range(ord('A'), ord('z')))
wrapper = self._get_wrapper(data)
read_data = b''
for chunk in wrapper:
read_data += chunk
self.assertEqual(data, read_data)
def test_info_wrapper_file_like_eats_error(self):
wrapper = self._get_wrapper(b'123456')
wrapper._format.eat_chunk.side_effect = Exception('fail')
data = b''
while True:
chunk = wrapper.read(3)
if not chunk:
break
data += chunk
# Make sure we got all the data despite the error
self.assertEqual(b'123456', data)
# Make sure we only called this once and never again after
# the error was raised
wrapper._format.eat_chunk.assert_called_once_with(b'123')
def test_info_wrapper_iter_like_eats_error(self):
fake_fmt = mock.create_autospec(format_inspector.get_inspector('raw'))
wrapper = format_inspector.InfoWrapper(iter([b'123', b'456']),
fake_fmt)
fake_fmt.eat_chunk.side_effect = Exception('fail')
data = b''
for chunk in wrapper:
data += chunk
# Make sure we got all the data despite the error
self.assertEqual(b'123456', data)
# Make sure we only called this once and never again after
# the error was raised
fake_fmt.eat_chunk.assert_called_once_with(b'123')
def test_get_inspector(self):
self.assertEqual(format_inspector.QcowInspector,
format_inspector.get_inspector('qcow2'))
self.assertIsNone(format_inspector.get_inspector('foo'))
class TestFormatInspectorsTargeted(test.TestCase):
def _make_vhd_meta(self, guid_raw, item_length):
# Meta region header, padded to 32 bytes
data = struct.pack('<8sHH', b'metadata', 0, 1)
data += b'0' * 20
# Metadata table entry, 16-byte GUID, 12-byte information,
# padded to 32-bytes
data += guid_raw
data += struct.pack('<III', 256, item_length, 0)
data += b'0' * 6
return data
def test_vhd_table_over_limit(self):
ins = format_inspector.VHDXInspector()
meta = format_inspector.CaptureRegion(0, 0)
desired = b'012345678ABCDEF0'
# This is a poorly-crafted image that specifies a larger table size
# than is allowed
meta.data = self._make_vhd_meta(desired, 33 * 2048)
ins.new_region('metadata', meta)
new_region = ins._find_meta_entry(ins._guid(desired))
# Make sure we clamp to our limit of 32 * 2048
self.assertEqual(
format_inspector.VHDXInspector.VHDX_METADATA_TABLE_MAX_SIZE,
new_region.length)
def test_vhd_table_under_limit(self):
ins = format_inspector.VHDXInspector()
meta = format_inspector.CaptureRegion(0, 0)
desired = b'012345678ABCDEF0'
meta.data = self._make_vhd_meta(desired, 16 * 2048)
ins.new_region('metadata', meta)
new_region = ins._find_meta_entry(ins._guid(desired))
# Table size was under the limit, make sure we get it back
self.assertEqual(16 * 2048, new_region.length)

110
cinder/tests/unit/privsep/test_format_inspector.py Normal file
View File

@ -0,0 +1,110 @@
# Copyright 2024 Red Hat, Inc
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
from unittest import mock
from cinder.privsep import format_inspector as pfi
from cinder.tests.unit import test
class TestFormatInspectorHelper(test.TestCase):
@mock.patch('cinder.image.format_inspector.detect_file_format')
def test_get_format_if_safe__happy_path(self, mock_detect):
mock_inspector = mock.MagicMock()
mock_inspector.__str__.return_value = 'mock_fmt'
mock_safety = mock_inspector.safety_check
mock_safety.return_value = True
mock_backing = mock_inspector.safety_check_allow_backing_file
mock_detect.return_value = mock_inspector
test_path = mock.sentinel.path
fmt_name = pfi._get_format_if_safe(path=test_path,
allow_qcow2_backing_file=False)
self.assertEqual(fmt_name, 'mock_fmt')
mock_safety.assert_called_once_with()
mock_backing.assert_not_called()
@mock.patch('cinder.image.format_inspector.detect_file_format')
def test_get_format_if_safe__allow_backing(self, mock_detect):
mock_inspector = mock.MagicMock()
mock_inspector.__str__.return_value = 'qcow2'
mock_safety = mock_inspector.safety_check
mock_safety.return_value = False
mock_backing = mock_inspector.safety_check_allow_backing_file
mock_backing.return_value = True
mock_detect.return_value = mock_inspector
test_path = mock.sentinel.path
fmt_name = pfi._get_format_if_safe(path=test_path,
allow_qcow2_backing_file=True)
self.assertEqual(fmt_name, 'qcow2')
mock_safety.assert_called_once_with()
mock_backing.assert_called_once_with()
@mock.patch('cinder.image.format_inspector.detect_file_format')
def test_get_format_if_safe__backing_fail(self, mock_detect):
"""backing flag should only work for qcow2"""
mock_inspector = mock.MagicMock()
mock_inspector.__str__.return_value = 'mock_fmt'
mock_safety = mock_inspector.safety_check
mock_safety.return_value = False
mock_backing = mock_inspector.safety_check_allow_backing_file
mock_detect.return_value = mock_inspector
test_path = mock.sentinel.path
fmt_name = pfi._get_format_if_safe(path=test_path,
allow_qcow2_backing_file=True)
self.assertIsNone(fmt_name)
mock_safety.assert_called_once_with()
mock_backing.assert_not_called()
@mock.patch('cinder.image.format_inspector.detect_file_format')
def test_get_format_if_safe__allow_backing_but_other_problem(
self, mock_detect):
mock_inspector = mock.MagicMock()
mock_inspector.__str__.return_value = 'qcow2'
mock_safety = mock_inspector.safety_check
mock_safety.return_value = False
mock_backing = mock_inspector.safety_check_allow_backing_file
mock_backing.return_value = False
mock_detect.return_value = mock_inspector
test_path = mock.sentinel.path
fmt_name = pfi._get_format_if_safe(path=test_path,
allow_qcow2_backing_file=True)
self.assertIsNone(fmt_name)
mock_safety.assert_called_once_with()
mock_backing.assert_called_once_with()
@mock.patch('cinder.image.format_inspector.detect_file_format')
def test_get_format_if_safe__unsafe(self, mock_detect):
mock_inspector = mock.MagicMock()
mock_inspector.__str__.return_value = 'mock_fmt'
mock_safety = mock_inspector.safety_check
mock_safety.return_value = False
mock_backing = mock_inspector.safety_check_allow_backing_file
mock_detect.return_value = mock_inspector
test_path = mock.sentinel.path
fmt_name = pfi._get_format_if_safe(path=test_path,
allow_qcow2_backing_file=False)
self.assertIsNone(fmt_name)
mock_safety.assert_called_once_with()
mock_backing.assert_not_called()

228
cinder/tests/unit/test_image_utils.py
View File

@ -30,55 +30,186 @@ from cinder.volume import throttling
class TestQemuImgInfo(test.TestCase):
@mock.patch('cinder.privsep.format_inspector.get_format_if_safe')
@mock.patch('os.name', new='posix')
@mock.patch('oslo_utils.imageutils.QemuImgInfo')
@mock.patch('cinder.utils.execute')
def test_qemu_img_info(self, mock_exec, mock_info):
def test_qemu_img_info(self, mock_exec, mock_info, mock_detect):
mock_out = mock.sentinel.out
mock_err = mock.sentinel.err
test_path = mock.sentinel.path
mock_exec.return_value = (mock_out, mock_err)
mock_detect.return_value = 'mock_fmt'
output = image_utils.qemu_img_info(test_path)
mock_exec.assert_called_once_with('env', 'LC_ALL=C', 'qemu-img',
'info', '--output=json', test_path,
run_as_root=True,
mock_exec.assert_called_once_with(
'env', 'LC_ALL=C', 'qemu-img', 'info', '-f', 'mock_fmt',
'--output=json', test_path, run_as_root=True,
prlimit=image_utils.QEMU_IMG_LIMITS)
self.assertEqual(mock_info.return_value, output)
mock_detect.assert_called_once_with(path=test_path,
allow_qcow2_backing_file=False)
@mock.patch('cinder.privsep.format_inspector.get_format_if_safe')
@mock.patch('os.name', new='posix')
@mock.patch('oslo_utils.imageutils.QemuImgInfo')
@mock.patch('cinder.utils.execute')
def test_qemu_img_info_not_root(self, mock_exec, mock_info):
def test_qemu_img_info_qcow2_backing_ok(
self, mock_exec, mock_info, mock_detect):
mock_out = mock.sentinel.out
mock_err = mock.sentinel.err
test_path = mock.sentinel.path
mock_exec.return_value = (mock_out, mock_err)
mock_detect.return_value = 'qcow2'
output = image_utils.qemu_img_info(
test_path, allow_qcow2_backing_file=True)
mock_exec.assert_called_once_with(
'env', 'LC_ALL=C', 'qemu-img', 'info', '-f', 'qcow2',
'--output=json', test_path, run_as_root=True,
prlimit=image_utils.QEMU_IMG_LIMITS)
self.assertEqual(mock_info.return_value, output)
mock_detect.assert_called_once_with(path=test_path,
allow_qcow2_backing_file=True)
@mock.patch('cinder.privsep.format_inspector.get_format_if_safe')
@mock.patch('os.name', new='posix')
@mock.patch('oslo_utils.imageutils.QemuImgInfo')
@mock.patch('cinder.utils.execute')
def test_qemu_img_info_raw_not_luks(self, mock_exec, mock_info,
mock_detect):
"""To determine if a raw image is luks, we call qemu-img twice."""
mock_out = mock.sentinel.out
mock_err = mock.sentinel.err
test_path = mock.sentinel.path
mock_exec.side_effect = [(mock_out, mock_err),
# it's not luks, so raise an error
processutils.ProcessExecutionError]
mock_detect.return_value = 'raw'
mock_data = mock.Mock()
mock_data.file_format = 'raw'
mock_info.return_value = mock_data
first = mock.call(
'env', 'LC_ALL=C', 'qemu-img', 'info', '-f', 'raw',
'--output=json', test_path, run_as_root=True,
prlimit=image_utils.QEMU_IMG_LIMITS)
second = mock.call(
'env', 'LC_ALL=C', 'qemu-img', 'info', '-f', 'luks',
'--output=json', test_path, run_as_root=True,
prlimit=image_utils.QEMU_IMG_LIMITS)
output = image_utils.qemu_img_info(test_path)
mock_exec.assert_has_calls([first, second])
mock_info.assert_called_once()
self.assertEqual(mock_info.return_value, output)
mock_detect.assert_called_once_with(path=test_path,
allow_qcow2_backing_file=False)
@mock.patch('cinder.privsep.format_inspector.get_format_if_safe')
@mock.patch('os.name', new='posix')
@mock.patch('oslo_utils.imageutils.QemuImgInfo')
@mock.patch('cinder.utils.execute')
def test_qemu_img_info_luks(self, mock_exec, mock_info, mock_detect):
# the format_inspector will identify the image as raw, but
# we will ask qemu-img for a second opinion, and it say luks
mock_out = mock.sentinel.out
mock_err = mock.sentinel.err
test_path = mock.sentinel.path
mock_exec.return_value = (mock_out, mock_err)
mock_detect.return_value = 'raw'
mock_data1 = mock.Mock(name='first_time')
mock_data1.file_format = 'raw'
mock_data2 = mock.Mock(name='second_time')
mock_data2.file_format = 'luks'
mock_info.side_effect = [mock_data1, mock_data2]
first = mock.call(
'env', 'LC_ALL=C', 'qemu-img', 'info', '-f', 'raw',
'--output=json', test_path, run_as_root=True,
prlimit=image_utils.QEMU_IMG_LIMITS)
second = mock.call(
'env', 'LC_ALL=C', 'qemu-img', 'info', '-f', 'luks',
'--output=json', test_path, run_as_root=True,
prlimit=image_utils.QEMU_IMG_LIMITS)
output = image_utils.qemu_img_info(test_path)
mock_exec.assert_has_calls([first, second])
self.assertEqual(2, mock_info.call_count)
self.assertEqual(mock_data2, output)
mock_detect.assert_called_once_with(path=test_path,
allow_qcow2_backing_file=False)
@mock.patch('cinder.privsep.format_inspector.get_format_if_safe')
@mock.patch('os.name', new='posix')
@mock.patch('oslo_utils.imageutils.QemuImgInfo')
@mock.patch('cinder.utils.execute')
def test_qemu_img_info_not_root(self, mock_exec, mock_info, mock_detect):
mock_out = mock.sentinel.out
mock_err = mock.sentinel.err
test_path = mock.sentinel.path
mock_exec.return_value = (mock_out, mock_err)
mock_detect.return_value = 'mock_fmt'
output = image_utils.qemu_img_info(test_path,
force_share=False,
run_as_root=False)
mock_exec.assert_called_once_with('env', 'LC_ALL=C', 'qemu-img',
'info', '--output=json', test_path,
run_as_root=False,
mock_exec.assert_called_once_with(
'env', 'LC_ALL=C', 'qemu-img', 'info', '-f', 'mock_fmt',
'--output=json', test_path, run_as_root=False,
prlimit=image_utils.QEMU_IMG_LIMITS)
self.assertEqual(mock_info.return_value, output)
mock_detect.assert_called_once_with(path=test_path,
allow_qcow2_backing_file=False)
@mock.patch('cinder.privsep.format_inspector.get_format_if_safe')
@mock.patch('cinder.image.image_utils.os')
@mock.patch('oslo_utils.imageutils.QemuImgInfo')
@mock.patch('cinder.utils.execute')
def test_qemu_img_info_on_nt(self, mock_exec, mock_info, mock_os):
def test_qemu_img_info_on_nt(self, mock_exec, mock_info, mock_os,
mock_detect):
mock_out = mock.sentinel.out
mock_err = mock.sentinel.err
test_path = mock.sentinel.path
mock_exec.return_value = (mock_out, mock_err)
mock_os.name = 'nt'
mock_detect.return_value = 'mock_fmt'
output = image_utils.qemu_img_info(test_path)
mock_exec.assert_called_once_with('qemu-img', 'info', '--output=json',
test_path, run_as_root=True,
prlimit=image_utils.QEMU_IMG_LIMITS)
mock_exec.assert_called_once_with(
'qemu-img', 'info', '-f', 'mock_fmt', '--output=json',
test_path, run_as_root=True, prlimit=image_utils.QEMU_IMG_LIMITS)
self.assertEqual(mock_info.return_value, output)
mock_detect.assert_called_once_with(path=test_path,
allow_qcow2_backing_file=False)
@mock.patch('cinder.privsep.format_inspector.get_format_if_safe')
@mock.patch('os.name', new='posix')
@mock.patch('cinder.utils.execute')
def test_qemu_img_info_malicious(self, mock_exec, mock_detect):
mock_out = mock.sentinel.out
mock_err = mock.sentinel.err
test_path = mock.sentinel.path
mock_exec.return_value = (mock_out, mock_err)
mock_detect.return_value = None
self.assertRaises(exception.Invalid,
image_utils.qemu_img_info,
test_path,
force_share=False,
run_as_root=False)
mock_exec.assert_not_called()
mock_detect.assert_called_once_with(path=test_path,
allow_qcow2_backing_file=False)
@mock.patch('cinder.utils.execute')
def test_get_qemu_img_version(self, mock_exec):
@ -176,6 +307,7 @@ class TestConvertImage(test.TestCase):
out_format = mock.sentinel.out_format
mock_info.return_value.file_format = 'qcow2'
mock_info.return_value.virtual_size = 1048576
mock_info.return_value.format_specific = {'data': {}}
throttle = throttling.Throttle(prefix=['cgcmd'])
with mock.patch('cinder.volume.volume_utils.check_for_odirect_support',
@ -2188,6 +2320,68 @@ class TestImageUtils(test.TestCase):
256)
@ddt.ddt(testNameFormat=ddt.TestNameFormat.INDEX_ONLY)
class TestQcow2ImageChecks(test.TestCase):
def setUp(self):
super(TestQcow2ImageChecks, self).setUp()
# Test data from:
# $ qemu-img create -f qcow2 fake.qcow2 1M
# $ qemu-img info -f qcow2 fake.qcow2 --output=json
qemu_img_info = '''
{
"virtual-size": 1048576,
"filename": "fake.qcow2",
"cluster-size": 65536,
"format": "qcow2",
"actual-size": 200704,
"format-specific": {
"type": "qcow2",
"data": {
"compat": "1.1",
"compression-type": "zlib",
"lazy-refcounts": false,
"refcount-bits": 16,
"corrupt": false,
"extended-l2": false
}
},
"dirty-flag": false
}'''
self.qdata = imageutils.QemuImgInfo(qemu_img_info, format='json')
def test_check_qcow2_image_no_problem(self):
image_utils.check_qcow2_image(fake.IMAGE_ID, self.qdata)
def test_check_qcow2_image_with_datafile(self):
self.qdata.format_specific['data']['data-file'] = '/not/good'
e = self.assertRaises(exception.ImageUnacceptable,
image_utils.check_qcow2_image,
fake.IMAGE_ID,
self.qdata)
self.assertIn('not allowed to have a data file', str(e))
def test_check_qcow2_image_with_backing_file(self):
# qcow2 backing file is done as a separate check because
# cinder has legitimate uses for a qcow2 with backing file
self.qdata.backing_file = '/this/is/ok'
image_utils.check_qcow2_image(fake.IMAGE_ID, self.qdata)
def test_check_qcow2_image_no_barf_bad_data(self):
# should never happen, but you never know ...
del self.qdata.format_specific['data']
e = self.assertRaises(exception.ImageUnacceptable,
image_utils.check_qcow2_image,
fake.IMAGE_ID,
self.qdata)
self.assertIn('Cannot determine format-specific', str(e))
self.qdata.format_specific = None
e = self.assertRaises(exception.ImageUnacceptable,
image_utils.check_qcow2_image,
fake.IMAGE_ID,
self.qdata)
self.assertIn('Cannot determine format-specific', str(e))
@ddt.ddt(testNameFormat=ddt.TestNameFormat.INDEX_ONLY)
class TestVmdkImageChecks(test.TestCase):
def setUp(self):
@ -2421,9 +2615,11 @@ class TestImageFormatCheck(test.TestCase):
}'''
self.qdata = imageutils.QemuImgInfo(qemu_img_info, format='json')
@mock.patch('cinder.image.image_utils.check_qcow2_image')
@mock.patch('cinder.image.image_utils.check_vmdk_image')
@mock.patch('cinder.image.image_utils.qemu_img_info')
def test_check_image_format_defaults(self, mock_info, mock_vmdk):
def test_check_image_format_defaults(self, mock_info, mock_vmdk,
mock_qcow2):
"""Doesn't blow up when only the mandatory arg is passed."""
src = mock.sentinel.src
mock_info.return_value = self.qdata
@ -2443,6 +2639,12 @@ class TestImageFormatCheck(test.TestCase):
image_utils.check_image_format(src)
mock_vmdk.assert_called_with(expected_image_id, self.qdata)
# Bug #2059809: a qcow2 should trigger an additional check
mock_info.reset_mock()
self.qdata.file_format = 'qcow2'
image_utils.check_image_format(src)
mock_qcow2.assert_called_with(expected_image_id, self.qdata)
@mock.patch('cinder.image.image_utils.qemu_img_info')
def test_check_image_format_uses_passed_data(self, mock_info):
src = mock.sentinel.src

31
cinder/tests/unit/volume/drivers/test_nfs.py
View File

@ -1361,7 +1361,8 @@ class NfsDriverTestCase(test.TestCase):
mock_read_info_file.assert_called_once_with(info_path)
mock_img_info.assert_called_once_with(snap_path,
force_share=True,
run_as_root=True)
run_as_root=True,
allow_qcow2_backing_file=True)
used_qcow = nfs_conf['nfs_qcow2_volumes']
if encryption:
mock_convert_image.assert_called_once_with(
@ -1491,7 +1492,8 @@ class NfsDriverTestCase(test.TestCase):
mock_img_utils.assert_called_once_with(vol_path,
force_share=True,
run_as_root=True)
run_as_root=True,
allow_qcow2_backing_file=True)
self.assertEqual('nfs', conn_info['driver_volume_type'])
self.assertEqual(volume.name, conn_info['data']['name'])
self.assertEqual(self.TEST_MNT_POINT_BASE,
@ -1506,13 +1508,34 @@ class NfsDriverTestCase(test.TestCase):
qemu_img_output = """{
"filename": "%s",
"format": "iso",
"virtual-size": 1073741824,
"virtual-size": 10737418240,
"actual-size": 173000
}""" % volume['name']
mock_img_info.return_value = imageutils.QemuImgInfo(qemu_img_output,
format='json')
self.assertRaises(exception.InvalidVolume,
self.assertRaisesRegex(exception.InvalidVolume,
"must be a valid raw or qcow2 image",
drv.initialize_connection,
volume,
None)
@mock.patch.object(image_utils, 'qemu_img_info')
def test_initialize_connection_raise_on_wrong_size(self, mock_img_info):
self._set_driver()
drv = self._driver
volume = self._simple_volume()
qemu_img_output = """{
"filename": "%s",
"format": "qcow2",
"virtual-size": 999999999999999,
"actual-size": 173000
}""" % volume['name']
mock_img_info.return_value = imageutils.QemuImgInfo(qemu_img_output,
format='json')
self.assertRaisesRegex(exception.InvalidVolume,
"virtual_size does not match",
drv.initialize_connection,
volume,
None)

58
cinder/tests/unit/volume/drivers/test_quobyte.py
View File

@ -273,7 +273,8 @@ class QuobyteDriverTestCase(test.TestCase):
mock_qemu_img_info.assert_called_with(mock.sentinel.image_path,
force_share=True,
run_as_root=True)
run_as_root=True,
allow_qcow2_backing_file=True)
@ddt.data(['/other_random_path', '/mnt'],
['/other_basedir/' + TEST_MNT_HASH + '/volume-' + VOLUME_UUID,
@ -961,10 +962,11 @@ class QuobyteDriverTestCase(test.TestCase):
else:
drv.extend_volume(volume, 3)
image_utils.qemu_img_info.assert_called_once_with(volume_path,
image_utils.qemu_img_info.assert_called_once_with(
volume_path,
force_share=True,
run_as_root=False
)
run_as_root=False,
allow_qcow2_backing_file=True)
image_utils.resize_image.assert_called_once_with(volume_path, 3)
def test_copy_volume_from_snapshot(self):
@ -1008,9 +1010,11 @@ class QuobyteDriverTestCase(test.TestCase):
drv._copy_volume_from_snapshot(snapshot, dest_volume, size)
drv._read_info_file.assert_called_once_with(info_path)
image_utils.qemu_img_info.assert_called_once_with(snap_path,
image_utils.qemu_img_info.assert_called_once_with(
snap_path,
force_share=True,
run_as_root=False)
run_as_root=False,
allow_qcow2_backing_file=True)
(mock_convert.
assert_called_once_with(src_vol_path,
dest_vol_path,
@ -1066,9 +1070,11 @@ class QuobyteDriverTestCase(test.TestCase):
drv._copy_volume_from_snapshot(snapshot, dest_volume, size)
drv._read_info_file.assert_called_once_with(info_path)
image_utils.qemu_img_info.assert_called_once_with(snap_path,
image_utils.qemu_img_info.assert_called_once_with(
snap_path,
force_share=True,
run_as_root=False)
run_as_root=False,
allow_qcow2_backing_file=True)
self.assertFalse(mock_convert.called,
("_convert_image was called but should not have been")
)
@ -1130,9 +1136,11 @@ class QuobyteDriverTestCase(test.TestCase):
drv._read_info_file.assert_called_once_with(info_path)
os_ac_mock.assert_called_once_with(
drv._local_volume_from_snap_cache_path(snapshot), os.F_OK)
image_utils.qemu_img_info.assert_called_once_with(snap_path,
image_utils.qemu_img_info.assert_called_once_with(
snap_path,
force_share=True,
run_as_root=False)
run_as_root=False,
allow_qcow2_backing_file=True)
(mock_convert.
assert_called_once_with(
src_vol_path,
@ -1193,9 +1201,11 @@ class QuobyteDriverTestCase(test.TestCase):
drv._copy_volume_from_snapshot(snapshot, dest_volume, size)
drv._read_info_file.assert_called_once_with(info_path)
image_utils.qemu_img_info.assert_called_once_with(snap_path,
image_utils.qemu_img_info.assert_called_once_with(
snap_path,
force_share=True,
run_as_root=False)
run_as_root=False,
allow_qcow2_backing_file=True)
(mock_convert.
assert_called_once_with(
src_vol_path,
@ -1264,9 +1274,11 @@ class QuobyteDriverTestCase(test.TestCase):
conn_info = drv.initialize_connection(volume, None)
drv.get_active_image_from_info.assert_called_once_with(volume)
image_utils.qemu_img_info.assert_called_once_with(vol_path,
image_utils.qemu_img_info.assert_called_once_with(
vol_path,
force_share=True,
run_as_root=False)
run_as_root=False,
allow_qcow2_backing_file=True)
self.assertEqual('raw', conn_info['data']['format'])
self.assertEqual('quobyte', conn_info['driver_volume_type'])
@ -1315,9 +1327,11 @@ class QuobyteDriverTestCase(test.TestCase):
mock_get_active_image_from_info.assert_called_once_with(volume)
mock_local_volume_dir.assert_called_once_with(volume)
mock_qemu_img_info.assert_called_once_with(volume_path,
mock_qemu_img_info.assert_called_once_with(
volume_path,
force_share=True,
run_as_root=False)
run_as_root=False,
allow_qcow2_backing_file=True)
mock_upload_volume.assert_called_once_with(
mock.ANY, mock.ANY, mock.ANY, upload_path, run_as_root=False,
store_id=None, base_image_ref=None, compress=True,
@ -1368,9 +1382,11 @@ class QuobyteDriverTestCase(test.TestCase):
mock_get_active_image_from_info.assert_called_once_with(volume)
mock_local_volume_dir.assert_called_with(volume)
mock_qemu_img_info.assert_called_once_with(volume_path,
mock_qemu_img_info.assert_called_once_with(
volume_path,
force_share=True,
run_as_root=False)
run_as_root=False,
allow_qcow2_backing_file=True)
mock_convert_image.assert_called_once_with(
volume_path, upload_path, 'raw', run_as_root=False)
mock_upload_volume.assert_called_once_with(
@ -1425,9 +1441,11 @@ class QuobyteDriverTestCase(test.TestCase):
mock_get_active_image_from_info.assert_called_once_with(volume)
mock_local_volume_dir.assert_called_with(volume)
mock_qemu_img_info.assert_called_once_with(volume_path,
mock_qemu_img_info.assert_called_once_with(
volume_path,
force_share=True,
run_as_root=False)
run_as_root=False,
allow_qcow2_backing_file=True)
mock_convert_image.assert_called_once_with(
volume_path, upload_path, 'raw', run_as_root=False)
mock_upload_volume.assert_called_once_with(

3
cinder/tests/unit/volume/drivers/test_remotefs.py
View File

@ -533,7 +533,8 @@ class RemoteFsSnapDriverTestCase(test.TestCase):
mock_qemu_img_info.assert_called_with(mock.sentinel.image_path,
force_share=False,
run_as_root=True)
run_as_root=True,
allow_qcow2_backing_file=True)
@ddt.data([None, '/fake_basedir'],
['/fake_basedir/cb2016/fake_vol_name', '/fake_basedir'],

10
cinder/volume/drivers/nfs.py
View File

@ -159,6 +159,16 @@ class NfsDriver(remotefs.RemoteFSSnapDriverDistributed):
msg = _('nfs volume must be a valid raw or qcow2 image.')
raise exception.InvalidVolume(reason=msg)
# Test if the size is accurate or if something tried to modify it
if info.virtual_size != volume.size * units.Gi:
LOG.error('The volume virtual_size does not match the size in '
'cinder, aborting as we suspect an exploit. '
'Virtual Size is %(vsize)s and real size is %(size)s',
{'vsize': info.virtual_size, 'size': volume.size})
msg = _('The volume virtual_size does not match the size in '
'cinder, aborting as we suspect an exploit.')
raise exception.InvalidVolume(reason=msg)
conn_info['data']['format'] = info.file_format
LOG.debug('NfsDriver: conn_info: %s', conn_info)
return conn_info

3
cinder/volume/drivers/remotefs.py
View File

@ -868,7 +868,8 @@ class RemoteFSSnapDriverBase(RemoteFSDriver):
info = image_utils.qemu_img_info(path,
force_share=force_share,
run_as_root=run_as_root)
run_as_root=run_as_root,
allow_qcow2_backing_file=True)
if info.image:
info.image = os.path.basename(info.image)
if info.backing_file:

19
releasenotes/notes/bug-2059809-disallow-qcow2-datafile-abc4e6d8be766710.yaml Normal file
View File

@ -0,0 +1,19 @@
---
security:
- |
Images in the qcow2 format with an external data file are now
rejected with an ``ImageUnacceptable`` error because such images
could be used in an exploit to expose host information. Given
that qcow2 external data files were never supported by Cinder,
this change should have no impact on users. See `Bug #2059809
<https://bugs.launchpad.net/cinder/+bug/2059809>`_ for details.
fixes:
- |
`Bug #2059809 <https://bugs.launchpad.net/cinder/+bug/2059809>`_:
Fixed issue where a qcow2 format image with an external data file
could expose host information. Such an image is now rejected with
an ``ImageUnacceptable`` error if it is used to create a volume.
Given that qcow2 external data files were never supported by
Cinder, the only use for such an image previously was to attempt
to steal host information, and hence this change should have no
impact on users.